package com.liyou.full.controller;

import com.liyou.full.common.Result;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.UUID;

/**
 * 文件上传和下载
 */
@Slf4j
@RestController
@RequestMapping("/common")
public class CommonController {

    /**
     * 文件上传
     *
     * @param file
     * @return
     */
    @Value("${full.path}")
    private String basePath;

    @PostMapping("/upload")
    public Result<String> upload(MultipartFile file) {
        //file是一个临时文件，需要转存到指定位置，否则本次请求完成后临时文件会删除
        log.info("上传文件名" + file.toString());
        //原始文件名
        String originalFilename = file.getOriginalFilename();
        //截取文件后缀名
        String suffix = originalFilename.substring(originalFilename.lastIndexOf("."));
        //使用UUID重新生成新的文件名，防止文件名重复造成文件覆盖
        String newFileName = UUID.randomUUID().toString() + suffix;
        //创建一个目录对象
        File dir = new File(basePath);
        //判断当前目录是否存在
        if (!dir.exists()) {
            //目录不存在
            dir.mkdirs();
        }
        try {
            //将临时文件转存到指定位置
            file.transferTo(new File(basePath + newFileName));
        } catch (IOException e) {
            e.printStackTrace();
        }
        //将临时文件转存到指定位置
        return Result.success(newFileName);
    }

    @GetMapping("/download")
    public void downLoad(String name, HttpServletResponse response){

        log.info("下载文件名{name}" + name);

        try {
            FileInputStream fileInputStream = new FileInputStream(new File(basePath + name));
            ServletOutputStream outputStream = response.getOutputStream();

            response.setContentType("image/jpeg");

            int len = 0;
            byte[] bytes = new byte[1024];
            while ((len = fileInputStream.read(bytes)) != -1) {
                outputStream.write(bytes, 0, len);
                //outputStream.flush();
            }

            outputStream.close();
            fileInputStream.close();

        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}
